Selective infusion of spatially controlled domains via vat photopolymerization 3D-printing for chemically diverse multimaterial parts

Creating multimaterial objects through vat photopolymerization (VP) is challenging due to difficulty transitioning between liquid resins. Multiwavelength VP has emerged as a prominent approach for achieving multimaterial parts through VP; however, the material scope has historically been limited to combinations of organic photo-resins. To address this limitation, we have developed a method that we refer to as infusion multimaterial actinic spatial control additive manufacturing (iMASC-AM). This technique uses dual wavelength light projection to create distinct material regions within a single printed part that display disparate affinity toward infusion of dissolved materials. Herein, we demonstrate the versatility of iMASC-AM with the infusion of organic dyes, silicone resins, and metal salts for patterned optical, mechanical, and conductive properties, respectively. Notably, mild thermal post-processing after infusion was found to reduce silver salts, leading to patterned combinations of electrically conductive and insulating domains and allowing for fabrication of functional circuits from a single print. The iMASC-AM method enables the creation of a wide variety of chemically diverse multimaterial parts with materials properties combinations that are generally inaccessible through VP. Creating multimaterial objects through vat photopolymerization is challenging due to difficulty transitioning between liquid resins and processing incompatibility between material classes. Here the authors develop infusion multimaterial actinic spatial control additive manufacturing, which uses dual wavelength light projection to create distinct material regions that can be selectively infused with a variety of organic and metallic materials.